Police deployed 2,500 officers ahead of the two-day visit of the Russian president, closing all main streets leading to the center of Athens.

Putin's plane landed in Greece with an hour-and-half-delay, under very tight security, while the Russian president’s plane was escorted by two Hellenic Air Force F-16s after it entered Athens airspace in honor of his arrival.

In the airport the Russian president, accompanied by a large delegation of businesspeople, including several Russian ministers and the CEOs of Gazprom and Rosneft, was welcomed by Defence Minister Panos Kammenos representing the Greek government.

Hellenic Republic President Prokopis Pavlopoulos later received the Russian president at the presidential mansion.

"Your visit to Greece comes at a crucial time, not only for our region but for all of Europe," Pavlopoulos told Putin upon his arrival.

"Close cooperation between Russia, the United States, and the European Union to end the war in Syria is exceptionally important for our time," he added.

For his part, Putin said it was time to "proceed with specific steps in order to exploit the opportunities that exist for strengthening bilateral relations."

Putin later met with Prime Minister Alexis Tsipras at Maximos Mansion, who later noted that “strengthening relations with Russia constitutes a strategic choice which is dictated both by the historically close, cultural and political ties, as well as the possibilities opening in front of us and the possibilities of strengthening stability in the region.”

For his part, Putin said, “In Moscow and St. Petersburg we have discussed analytically the prospects for economic cooperation. Of course there are many problems and the circumstances are difficult, but there are certainly good prospects.”

After a marathon closed-door meeting between the two officials, talks continued between the two delegations, focusing on strengthening bilateral economic and trade relations, upgrading political dialogue on international and regional developments and EU-Russia, NATO-Russia relations and cooperation in culture, education, science and technology.

The two sides also signed cooperation agreements on a political declaration for Greek-Russian dialogue on international and regional issues of mutual interest and a partnership declaration for modernization, in addition to agreements between the ministries of science, technology, tourism, meteorology, and agriculture.

The two sides also signed cooperation agreements between, Enterprise Greece and Invest in Russia, the University of Piraeus and the University of the Urals, and the Center for Renewable Energy Sources and the Russian Institute of Energy.

Hellenic Petroleum (ELPE) signed a memorandum of cooperation to obtain crude from Russian oil giant Rosneft.

“It is an important agreement which is part of the group's policy for extroversion. Thanks to this, important objectives have been achieved, which relate to finding adequate alternative sources of supply of petroleum products at very competitive prices,” said ELPE CEO Grigoris Stergioulis.

In a joint press conference, the two leaders expressed their gratitude to each other. Putin said that he had a meaningful meeting with the Greek side, adding that Greek-Russian cooperative relations continue with a progressive trend.

Asked how Turkish-Russian relations might be normalized, Putin said, “Even now I cannot understand why they did it [downed a Russian fighter jet last November].”

He added, "Our forces are not fighting in Syria against the normal regular forces, but against formations and we never thought that the Turkish fighter could shoot our own aircraft,” adding that not only did the aircraft crash but the pilot was also shot.

"This is a war crime," he said, adding that he had not gotten any explanations from the Turkish leadership.

“We heard,” he said, “that there is a desire to restore our relations and we also have such a desire,” adding, “We do our utmost to bring Russian-Turkish relations at a very high level, emphasizing that desire and statements are not enough for the restoration of relations. We still wait for explanations. Still there are none.”

Tsipras stated that Putin’s visit to Greece, after many years, is the culmination of a series of contacts and meetings at a high level which mark the restart of the two countries' relations.

“Today validated the enhanced political dialogue between the two countries at the highest level and we made some important steps with the signing of a series of memoranda of understanding. We proved that it can and there are positive memorandums,” the prime minister said, stressing that Greek-Russian dialogue may prove important as Russia plays an important role in a number of issues of particular importance to Greece and the wider region.

Putin will later meet with New Democracy leader Kyriakos Mitsotakis.

On Saturday Putin will depart for Thessalonica, where he will meet Foreign Minister Nikos Kotzias. Putin will then carry out a pilgrimage at the monastery on Mt. Athos, where there will be an official reception by President Pavlopoulos.